Today: - Announcements - Nutrient Lab Check-up - Lifecycle Review - Flowering Plant Diversity and Reproduction

1. Today:- Announcements- Nutrient Lab Check-up- Lifecycle Review- Flowering Plant Diversity and Reproduction

3. Scholarships Available! Are you planning to major in science, engineering or math? Apply for NSCC’s Onsight Scholarships!Onsight Scholars receive support through membership in the RST Academy, including a faculty mentor and up to $2000/quarter to help with your expenses! Who’s eligible? You must: Be pursuing a degree in science, engineering or math Be a US citizen or permanent resident Demonstrate financial need (complete your FAFSA) Submit your completed application by May 27, 2011 To learn more, check out http://seattlecolleges.com/RST Or contact Ann Murkowski amurkowski@sccd.ctc.edu

4. Checking in on our Nutrient Deficiency Experiment… • Due Thursday: • A 1-2 paragraph description of your nutrient and effects of deficiency in this nutrient. • Start collecting your sources! Include 2+ references with this description. (3+ are required for the final paper).

5. Report Out: Thoughts/Comments on Sexual Encounters of the Floral Kind or our greenhouse tour?

6. Lifecycle Review: • With a partner, complete lifecycle 1, a generic plant lifecycle for all plants. What does each structure represent? Are they diploid or haploid? Sporophyte or gametophyte? • Show Ann and move to lifecycle 2, a quick review. Again, label parts and ploidy. • Move to lifecycle 3!

7. Double

8. Lab Review: What is this? What’s shown at the arrow? Is this haploid or diploid? Explain.

10. More on the Angiosperms!

11. Minor Modifications Both gymnosperms and angiosperms use tracheids in their xylem Angiosperms also use vessel elements, and reinforce with fiber cells!

12. Major Modification: the Flower • 4 circles of modified leaves: • Sepals • Petals • Stamens • Carpels

13. Fruits are Mature Ovaries Fruits protect seeds and aid in their dispersal Ovary wall becomes the pericarp (thickened wall of the fruit)

14. Fruits are Mature Ovaries

15. Hypothetical Origin of the Carpel

16. Types of Fruit 1. Simple Fruit- derived from a single ovary 2. Aggregate Fruit- derived from a single flower with several carpels 3. Multiple Fruit- develops from a group of flowers tightly clustered together (inflorescence)

18. Inferior or Superior Ovaries?

20. The Angiosperms Evolution of the Flower! Traditional taxonomy = 2 Classes Monocots and Dicots Jack-in-the-Pulpit, Arisaema triphyllum

21. Not Monophyletic!

22. Angiosperms Shape Evolution By the end of the Cretaceous (65 mya) angiosperms are the dominant plants on Earth. Plants and their pollinators and dispersers are a good example of coevolution (mutual evolutionary influence) Examples??

23. Other Notes about Angiosperms - Ecologically important - Major human food source - Source of unique secondary compounds (drugs!) Diversity is a non-renewable resource!

25. A Closer Look at Angiosperm Reproduction:What’s unusual about fertilization in this group?

26. A Closer Look at Angiosperm Reproduction The division into the terminal and basal cells establishes the polarity of the embryo.

27. A Closer Look at Angiosperm Reproduction: Seed Development • As it matures, the seed dehydrates, entering dormancy • Seeds respond to a variety of signals to end dormancy (rainfall, fire, light, digestion • This allows for seed banks within soils!

28. A Closer Look at Angiosperm Reproduction: Seed Development • Germination also depends in imbibition(uptake of water)

29. Role of Asexual Reproduction What are two serious limitations of this strategy? 47,000 stems of genetically identical (male) aspens?! This creosote bush is believed to have germinated from a single seed 11,700 years ago!

30. Asexual Reproduction via Apomixis! • 2n egg is formed and develops without ever being fertilized • Cells from the 2n ovule develop into an embryo • In a rare cypress, the pollen grains are 2n and can develop into an embryo when they land on either female cones of their own species, or cones of a more common species of cypress!! (paternal apomixis)

31. Preventing Self-Fertilization • What do you notice about the flowers from these two, separate, holly plants? • Is self-fertilization possible?? • Is this plant monoecious or dioecious?

32. Preventing Self-Fertilization

33. Preventing Self-Fertilization Self-incompatibility (SI) is the most common mechanism to prevent self-fertilization

34. Preventing Self-Fertilization Timing can also prevent self-fertilization. In this eucalyptus flower, the anthers mature long before the stigma is receptive. Photo: Brian Johnston

35. Other Forms of “Reproduction”

36. Other Forms of “Reproduction” This ability to grow an entire plant from single cell enables transgenic plants to be created much more easily!

37. Plant Biotechnology? ??

38. One Application: Biofuels • One Approach:1. Find, breed, or modify plants to have weaker cell walls. • 2. Use cellulase enzymes to convert the cellulose into sugar. • Ferment the sugar into ethanol. Switchgrass in the research lab of Professor Pam Ronald at UC Davis.

39. One Application: Insect Resistance

40. One Application: Increased Nutrition? http://www.youtube.com/watch?v=sbxA4WlkUP8&feature=related

41. One Application: Increased Nutrition?

42. Risks and Concerns? • Human Health Impacts? • Effects on Non-Target Organisms? • Transgene escape?